Low power and Lossy Networks (LLNs), e.g., sensor networks, have a myriad of applications, such as Smart Grids and Smart Cities. Various challenges are presented with LLNs, such as lossy links, low bandwidth, battery operation, low memory and/or processing capability, etc. One example routing solution implemented to address LLN challenges is a protocol called Routing Protocol for LLNs or “RPL,” which is a distance vector routing protocol that builds a Destination Oriented Directed Acyclic Graph (DODAG, or simply DAG) in addition to a set of features to bound the control traffic, support local (and slow) repair, etc. The RPL architecture provides a flexible method by which each node performs DODAG discovery, construction, and maintenance.
For a number of reasons, the LLN Border Router (LBR) or DAG root typically represents the network's bottleneck. For instance, the LBR may be both a communication bottleneck (e.g., where a vast majority of traffic flows through the LBR) as well as a memory bottleneck (e.g., storing per-node state for each node in the network). In addition, the effect of LBR failures on an LLN can be particularly problematic to mitigate, particularly since all of the nodes within the LLN of the failed LBR must migrate to a new LLN and associated LBR.